Sonntag, 16. August 2015

The spiral in a snail's shell is the same mathematically as
the spiral in the Milky Way galaxy, and it's also the same mathematically as
the spirals in our DNA. It's the same ratio that you'll find in very basic
music that transcends cultures all over the world.

Snails are invertebrates, which are animals with no
backbones. The shell on the snail helps protect it, and also reduces the loss
of water by evaporation. Shells have many different shapes, sizes, and colours.
Snails do not breathe through their mouths, instead they have a breathing hole
under their shells.

As the snail grows, so does its calcium carbonate shell. The
shell grows additively, by the addition of new calcium carbonate, which is
secreted by glands located in the snail's mantle. The new material is added to
the edge of the shell aperture (the opening of the shell). Therefore the centre
of the shell's spiral was made when the snail was younger, and the outer part
when the snail was older. When the snail reaches full adult size, it may build
a thickened lip around the shell aperture. At this point the snail stops
growing, and begins reproducing. A snails "foot" is a muscle which
allows it to move slowly across the ground. The foot puts out ('exudes') slime,
which eases the snail's movement, leaving a trail. Snails can absorb mineral
nutrients through their foot by simply sitting on a rock containing it.

The head is attached to the foot. The mouth is like a cheese
grater. It is called a radula. It is used for cutting food. On the radula there
are little teeth. On the head there are 15 mm stalks. At the end of the stalks
are snail’s eyes, though they do not see very well.

Snails are invertebrates, which are animals with no
backbones. The shell on the snail helps protect it, and also reduces the loss
of water by evaporation. Shells have many different shapes, sizes, and colours.
Snails do not breathe through their mouths, instead they have a breathing hole
under their shells.

A snails "foot" is a muscle which allows it to
move slowly across the ground. The foot puts out ('exudes') slime, which eases
the snail's movement, leaving a trail. Snails can absorb mineral nutrients
through their foot by simply sitting on a rock containing it.

The snail family is big and believed aprox. 200,000 species
of mollusks (incl. Snails), 50,000
classified.